#pragma once
#include <string>
#include <iostream>
using namespace std;
class SalesItem{
public:
	SalesItem();
	virtual ~SalesItem();
	string isbn();
	SalesItem& operator=(SalesItem& si);
	void combine(SalesItem& si);
	friend ostream& operator<<(ostream& os,SalesItem& si);
	friend istream& operator>>(istream& is,SalesItem& si);
	
private:
	string _bookNo;
	unsigned int _unitsSold =0;
	double _sellingPrice=0;
	double _salesPrice=0;
	double _discount =0;
};
